John Travolta shares heartbreaking tribute after death of Grease co-star Olivia Newton-John

John Travolta has penned a touching tribute to his Grease co-star Olivia Newton-John in the wake of her death at age 73.

The Aussie icon's family confirmed the sad news on August 9, with Travolta wasting no time to thank his incredible leading lady.

"My dearest Olivia, you made all of our lives so much better," Travolta said.

"Your impact was incredible. I love you so much. We will see you down the road and we will all be together again."

He added: "Yours from the first moment I saw you and forever! Your Danny, your John."

Newton-John hit the big time alongside Travolta in the 1978 high school classic Grease, where she starred as Sandy alongside Travolta's Danny.

The musical catapulted her into superstardom, gaining an army of fans around the world.

In recent years, the Australian actor had been very open about her breast cancer diagnosis, which she received in 1992.

Throughout her diagnosis, she underwent numerous treatments, including a mastectomy, chemotherapy and breast reconstruction.

Since news of her death was announced, many of the singer's fans have taken to social media to offer their condolences to her family.

One said: "This one hurts deeply. My inner 11 year self is shattered. Farewell Olivia Newton-John."

Echoing the shock, another commented: "Rest In Peace Olivia Newton-John. Fly high in Greased Lightning."

"RIP Olivia Newton-John - a generation of '70s kids will never forget you," put a third.

While another added: "Grease is a movie I’ll never get enough of. Those black leggings, that blonde curly hair, that incredible voice that I tried to imitate as child in front of mirror. RIP Dame Olivia Newton-John who has died at age of 73."

In a post to the Grease star's Facebook page, her husband John Easterling praised her for being a 'symbol of triumphs and hope'.

He also asked people to give the family some privacy at this difficult time.

Mr Easterling said: "Dame Olivia Newton-John passed away peacefully at her ranch in Southern California this morning, surrounded by family and friends.

"We ask that everyone please respect the family’s privacy during this very difficult time.

"Olivia has been a symbol of triumphs and hope for over 30 years sharing her journey with breast cancer.

"Her healing inspiration and pioneering experience with plant medicine continues with the Olivia Newton-John Foundation Fund, dedicated to researching plant medicine and cancer."

In lieu of flowers, the family asks that any donations be made in her memory to the Olivia Newton-John Foundation Fund.